[CS] Remove obsolete check for a type variable

We no longer need to check for a type variable
here, it no longer regresses diagnostics. Also,
while here, let's bump the impact for an
Any/AnyObject missing conformance, as that's
unlikely going to be helpful since they cannot
conform to protocols even if the user wanted them
to.

Author: hamishknight

lib/Sema/CSSimplify.cpp

@@ -2755,24 +2755,17 @@ assessRequirementFailureImpact(ConstraintSystem &cs, Type requirementType,
     }
   }
 
-  // Increase the impact of a conformance fix for a standard library
-  // or foundation type, as it's unlikely to be a good suggestion.
-  //
-  // Also do the same for the builtin compiler types Any and AnyObject,
-  // which cannot conform to protocols.
-  //
-  // FIXME: We ought not to have the is<TypeVariableType>() condition here, but
-  // removing it currently regresses the diagnostic for the test case for
-  // rdar://60727310. Once we better handle the separation of conformance fixes
-  // from argument mismatches in cases like
-  // https://github.com/apple/swift/issues/54877, we should be able to remove
-  // it from the condition.
-  if ((requirementType->is<TypeVariableType>() && resolvedTy->isStdlibType()) ||
-      resolvedTy->isAny() || resolvedTy->isAnyObject() ||
-      getKnownFoundationEntity(resolvedTy->getString())) {
-    if (locator.isForRequirement(RequirementKind::Conformance)) {
+  if (locator.isForRequirement(RequirementKind::Conformance)) {
+    // Increase the impact of a conformance fix for a standard library
+    // or foundation type, as it's unlikely to be a good suggestion.
+    if (resolvedTy->isStdlibType() ||
+        getKnownFoundationEntity(resolvedTy->getString())) {
       impact += 2;
     }
+    // Also do the same for the builtin compiler types Any and AnyObject, but
+    // bump the impact even higher as they cannot conform to protocols at all.
+    if (resolvedTy->isAny() || resolvedTy->isAnyObject())
+      impact += 4;
   }
 
   // If this requirement is associated with an overload choice let's

test/Constraints/optional.swift

@@ -435,8 +435,8 @@ func test_force_unwrap_not_being_too_eager() {
 // rdar://problem/57097401
 func invalidOptionalChaining(a: Any) {
   a == "="? // expected-error {{cannot use optional chaining on non-optional value of type 'String'}}
-  // expected-error@-1 {{type 'Any' cannot conform to 'Equatable'}}
-  // expected-note@-2 {{requirement from conditional conformance of 'Any?' to 'Equatable'}} expected-note@-2 {{only concrete types such as structs, enums and classes can conform to protocols}}
+  // expected-error@-1 {{binary operator '==' cannot be applied to operands of type 'Any' and 'String?'}}
+  // expected-note@-2 {{overloads for '==' exist}}
 }
 
 /// https://github.com/apple/swift/issues/54739